Problem of the Week:
Making Change at the Boutique Shop(Teacher Page)

In the Boutique Shop, you must
determine the change a customer receives from $5.00 for each purchase and
decide what coins you use to make the change. You have quarters,
dimes, nickels, and pennies.* (Below is a list
of 8 possibilities.)

Whats the most number of coins you can use to
find this change if you have a limit of 9 of any particular coin? (18)

Why can you use only 8 pennies or 3 pennies?
(Why not 9, 7, 6, 5, 4, 2, 1, or 0?) Try some of
the numbers in parenthesis and see what happens. For example, if you have
9 pennies, then you have to make $.69 with the remaining coins. How do
you make $.69 with only quarters, dimes and nickels? The amount that you
make with the combinations of these three coins has to be a multiple of
5. So if you subtract the number of pennies from your required change,
then that number has to be a multiple of 5.